论文部分内容阅读
目的研究肺炎克雷伯菌临床菌株gyrA和parC基因喹诺酮耐药决定区(QRDR)突变与环丙沙星耐药的相关性。方法采用琼脂稀释法检测124株临床菌株对环丙沙星的最小抑菌浓度(MIC),K-B法检测临床菌株对其他13种抗菌药物的耐药性,测序分析50株临床菌株gyrA和parC基因QRDR喹诺酮耐药决定区。结果 124株临床菌株对环丙沙星耐药和敏感的分别有56株和68株。未见亚胺培南和美洛培南耐药菌株,氨苄西林和哌拉西林总耐药率达99.2%和96.0%。所有敏感株对环丙沙星的MICs≤1mg/L,耐药株对环丙沙星的MICs≥4 mg/L。环丙沙星耐药株gyrA基因突变发生率明显高于敏感株(P<0.05),且Ser83突变发生与MICs大小有关。环丙沙星耐药株parC基因Ser80突变发生率明显高于敏感株(P<0.01),parC基因Ser80突变与耐药程度密切相关。结论亚胺培南和美洛培南可推荐用于本地区肺炎克雷伯菌感染的治疗,gyrA和parC基因突变在环丙沙星耐药中起重要作用。
Objective To study the relationship between quinolone-resistant (gyrA) and parC gene mutations of Klebsiella pneumoniae clinical isolates and ciprofloxacin resistance. Methods The minimum inhibitory concentration (MIC) of ciprofloxacin against 124 strains of clinical isolates was determined by agar dilution method. The antibiotic resistance of 13 strains of antibacterials was tested by KB method. The gyrA and parC genes of 50 strains were sequenced QRDR quinolone resistance area. Results 124 strains of clinical isolates were sensitive and resistant to ciprofloxacin 56 and 68, respectively. No imipenem and meropenem resistant strains were found. The rates of resistance to ampicillin and piperacillin were 99.2% and 96.0%, respectively. MICs of all sensitive strains to ciprofloxacin were less than or equal to 1 mg / L, MICs of resistant strains to ciprofloxacin were more than or equal to 4 mg / L. The incidence of gyrA gene mutation in ciprofloxacin resistant strains was significantly higher than that in susceptible strains (P <0.05), and the occurrence of Ser83 mutation was related to the size of MICs. The incidence of Ser80 mutation of parC gene in ciprofloxacin resistant strains was significantly higher than that in susceptible strains (P <0.01). Ser80 mutation of parC gene was closely related to the drug resistance. Conclusion Imipenem and meropenem may be recommended for the treatment of Klebsiella pneumonia in this region. The gyrA and parC gene mutations play an important role in the resistance of ciprofloxacin.